Alert archive / Oklahoma / Tornado Watches in 2015

Tornado Watch 36

April 8, 201522 counties in Kansas; 31 counties in Oklahoma; 4 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 8, 2015, 3:37 PM CDT for 22 counties in Kansas; 31 counties in Oklahoma; 4 counties in Texas. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued
Apr 8, 2015, 3:37 PM CDT (20:37 UTC)
Expired
Apr 8, 2015, 11:17 PM CDT
In force
8 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
65 kt
All 57 counties

Allen County, KS, Barber County, KS, Butler County, KS, Chase County, KS, Chautauqua County, KS, Cowley County, KS, Elk County, KS, Greenwood County, KS, Harper County, KS, Harvey County, KS, Kingman County, KS, Labette County, KS, Marion County, KS, McPherson County, KS, Montgomery County, KS, Neosho County, KS, Reno County, KS, Rice County, KS, Sedgwick County, KS, Sumner County, KS, Wilson County, KS, Woodson County, KS, Alfalfa County, OK, Beckham County, OK, Blaine County, OK, Caddo County, OK, Canadian County, OK, Creek County, OK, Custer County, OK, Dewey County, OK, Ellis County, OK, Garfield County, OK, Grant County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Lincoln County, OK, Logan County, OK, Major County, OK, Noble County, OK, Oklahoma County, OK, Osage County, OK, Pawnee County, OK, Payne County, OK, Roger Mills County, OK, Tulsa County, OK, Washington County, OK, Washita County, OK, Woods County, OK, Woodward County, OK, Childress County, TX, Collingsworth County, TX, Hall County, TX, Hardeman County, TX

The radar

The Vance AFB radar (KVNX), 48 km from the middle of the area, began a volume at 20:37 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
70%
One or more EF2 to EF5 tornadoes
40%
Ten or more severe wind reports
80%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
90%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

31 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 8, 3:42 PM CDTSevere Thunderstorm WarningICTAllen, Neosho21 min
Apr 8, 3:58 PM CDTSevere Thunderstorm WarningICTAllen17 min
Apr 8, 4:30 PM CDTSevere Thunderstorm WarningOUNWoods, Woodward30 min
Apr 8, 4:32 PM CDTSevere Thunderstorm WarningOUNWoods, Woodward28 min
Apr 8, 4:46 PM CDTSevere Thunderstorm WarningOUNCuster, Dewey, Ellis, Roger Mills44 min
Apr 8, 4:52 PM CDTSevere Thunderstorm WarningDDCBarber53 min
Apr 8, 4:55 PM CDTSevere Thunderstorm WarningOUNWoods35 min
Apr 8, 4:57 PM CDTSevere Thunderstorm WarningOUNHarper, Woods33 min
Apr 8, 5:21 PM CDTSevere Thunderstorm WarningOUNHarper, Woods, Woodward39 min
Apr 8, 5:24 PM CDTSevere Thunderstorm WarningOUNDewey, Ellis, Roger Mills, Woodward51 min
Apr 8, 5:25 PM CDTSevere Thunderstorm WarningOUNHarper, Woods35 min
Apr 8, 5:50 PM CDTSevere Thunderstorm WarningICTKingman, Reno22 min
Apr 8, 5:55 PM CDTTornado WarningOUNDewey, Ellis, Roger Mills, Woodward50 min
Apr 8, 6:15 PM CDTTornado WarningDDCBarber, Comanche30 min
Apr 8, 6:41 PM CDTTornado WarningDDCBarber, Comanche34 min
Apr 8, 6:42 PM CDTSevere Thunderstorm WarningOUNDewey, Major, Woodward29 min
Apr 8, 7:07 PM CDTTornado WarningDDCBarber38 min
Apr 8, 7:35 PM CDTTornado WarningDDCBarber25 min
Apr 8, 7:37 PM CDTSevere Thunderstorm WarningICTKingman38 min
Apr 8, 7:41 PM CDTSevere Thunderstorm WarningOUNBeckham, Roger Mills34 min
Apr 8, 7:54 PM CDTSevere Thunderstorm WarningICTKingman, Reno, Sedgwick51 min
Apr 8, 8:11 PM CDTSevere Thunderstorm WarningOUNBeckham, Custer, Dewey, Roger Mills49 min
Apr 8, 8:15 PM CDTSevere Thunderstorm WarningICTKingman30 min
Apr 8, 8:32 PM CDTTornado Warning Tornado observedICTSedgwick28 min
Apr 8, 8:44 PM CDTSevere Thunderstorm WarningOUNBeckham, Roger Mills31 min
Apr 8, 8:46 PM CDTSevere Thunderstorm WarningICTKingman, Reno, Sedgwick29 min
Apr 8, 8:53 PM CDTTornado WarningICTHarvey, Sedgwick26 min
Apr 8, 8:53 PM CDTSevere Thunderstorm WarningOUNBeckham, Blaine, Custer, Dewey, Roger Mills52 min
Apr 8, 8:58 PM CDTTornado Warning Tornado observedOUNCuster, Dewey47 min
Apr 8, 9:04 PM CDTSevere Thunderstorm WarningOUNBaylor, Foard, Hardeman, Knox, Wilbarger56 min
Apr 8, 9:42 PM CDTSevere Thunderstorm WarningOUNBlaine, Custer, Dewey48 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 8.6 hours before the alert went out and 161 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2015-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1989 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2015-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 328 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1989 J/kg
Mixed-layer CIN
-278 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
328 m²/s²
0-3 km storm-relative helicity
298 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

006 
WWUS20 KWNS 082040
SEL6  
SPC WW 082040
KSZ000-OKZ000-TXZ000-090500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 36
NWS STORM PREDICTION CENTER NORMAN OK
340 PM CDT WED APR 8 2015

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTH CENTRAL AND SOUTHEASTERN KANSAS
  WESTERN...CENTRAL...AND NORTHERN OKLAHOMA
  NORTHWEST TEXAS

* EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 340 PM UNTIL MIDNIGHT
  CDT.

* PRIMARY THREATS INCLUDE...
  A FEW TORNADOES LIKELY WITH A COUPLE INTENSE TORNADOES POSSIBLE
  WIDESPREAD DAMAGING WINDS LIKELY WITH ISOLATED SIGNIFICANT GUSTS
    TO 75 MPH POSSIBLE
  WIDESPREAD LARGE HAIL LIKELY WITH ISOLATED VERY LARGE HAIL
    EVENTS TO 3 INCHES IN DIAMETER POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 60 MILES WEST OF CLINTON
OKLAHOMA TO 45 MILES NORTH NORTHEAST OF BARTLESVILLE OKLAHOMA. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU6).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 33...WW 34...WW 35...

DISCUSSION...TSTMS/SUPERCELLS EXPECTED TO DEVELOP ENE ACROSS WW AREA
THROUGH LATE EVE AS CONVERGENCE AND ASCENT FOCUS INVOF DEVELOPING
SRN KS SFC WAVE AND ASSOCIATED STNRY FRONT. MORE ISOLD STORMS
EXPECTED TO FORM SSWWD ALONG TRAILING DRY LINE. TORNADO THREAT MAY
INCREASE AFTER SUNSET AS SSWLY LLJ STRENGTHENS IN RESPONSE TO BOTH
DIURNAL CYCLE AND CONTINUE ENE MOVEMENT OF SWRN U.S. UPR LVL SPEED
MAX.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 25040.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 7, 8:24 PM CDTSevere Thunderstorm WatchSPCAllen, Bourbon, Chautauqua, Cherokee, Cowley, Crawford and 7 more5 hr
Apr 7, 10:13 PM CDTMesoscale DiscussionSPCAllen, Bourbon, Chautauqua, Cherokee, Crawford, Elk and 5 more2 hr
Apr 8, 6:17 AM CDTMesoscale DiscussionSPCBourbon, Linn, Miami88 min
Apr 8, 2:21 PM CDTMesoscale DiscussionSPCAllen, Anderson, Bourbon, Chautauqua, Cherokee, Coffey and 12 more114 min
Apr 8, 2:47 PM CDTSevere Thunderstorm WatchSPCAllen, Anderson, Bourbon, Chautauqua, Cherokee, Coffey and 13 more4 hr
Apr 8, 5:31 PM CDTMesoscale DiscussionSPCChase, Harvey, Kingman, Marion, Pratt, Reno59 min
Apr 8, 5:45 PM CDTMesoscale DiscussionSPCJohnson, Miami60 min
Apr 8, 6:40 PM CDTMesoscale DiscussionSPCBorden, Cottle, Dickens, Fisher, Foard, Garza and 11 more65 min

Nearby

Tornado Watches in Oklahoma, 2015Tornado Watches in Kansas, 2015Tornado Watches in Texas, 2015Every tornado watch in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.